Antenna heat placement



July 11, 1961 R. s. TAYLOR 2,992,313

ANTENNA HEAT PLACEMENT Filed June 24, 1958 l: 1 H i; I8

l5 INVENTOR ROBERT s. TAYLOR X 2022 ATTORNEY United States Patent 2,992,313 ANTENNA HEAT PLACEMENT Robert S. Taylor, Evansville, Ind. (2906 Cedarview Drive, Austin 4, Tex.) Filed June 24, 1958, Ser. No. 744,245 1 Claim. (Cl. 219-19) This invention relates to heat placement and more particularly to an electrical conductor such as an antenna of which the surface is maintained at temperatures above the ambient with an hermetically sealed duct containing halogenated hydrocarbon fluid which in liquid phase drains to a part which is heated to keep the duct filled with hot vapor.

Distortion or failure of radio, television, or radar by formation of ice on the antenna is annoying at anytime, but in navigation the consequences can be serious. The object of this invention is to obviate such hazard by providing a heat placement system that prevents the ice formation.

The object and advantages of the invention will be more fully understood from reference to the description taken in connection with the drawing which is an elevation partly in cross section of a so-called buggy whip type of antenna embodying the invention.

Referring to the drawing, an antenna is formed by a metal tube spun closed and soldered at its upper end 11 to hermetically seal this end of the duct 12 within the antenna tube. The other end of the antenna tube 10 is fitted with a threaded plug 13 having a center bore or passageway 14. The plug 13 is hermetically sealed to the tube 10 as by silver solder, and a soft copper tube 15 is similarly joined to the plug 13 to form an extension of the passage 14.

The hollow antenna is evacuated by a pump connected to the tube 15 and then a charge of dichlorodifluoromethane, or other suitable halogenated hydrocarbon fluid, is introduced into the hollow conductor through the tube 15 which is then pinched closed and hermetically sealed by solder at the end 16.

An insulating bushing 17 of porcelain or other suitable dielectric material is secured on the lower end of the antenna 10 between a ledge 18, formed by a washer silver soldered on the hollow rod, and a nut 19 threaded on the plug 13 and holding a hard washer 20 and a soft washer 21 against the bottom of the bushing 17. The antenna lead 22 is secured on the plug 13 by a second nut 23. A soft washer or gasket 32 is located between the ledge 18 and the upper end of the bushing 17.

Around the antenna tube 10 within the bushing 17 is located an annular electric heating element 24 from which leads 25 and 26 project through slots in the lower edge of the bushing for connection to a suitable source of electric current for operating the heater.

The antenna is shown mounted on the skin sheet 27 of an aeroplane. The bushing 17 has an annular shoulder 28 which abuts a soft washer 29 and the inside of the sheet 27 with the bushing and antenna projecting through a hole in the sheet. A retaining ring 30 engages the shoulder 28 and is secured to the sheet 27 by four bolts 31.

The antenna can be mounted in any position such that liquid drains by gravity down the duct 12 to the vicinity of the heater 24. With the latter in operation the fluid in liquid phase is heated to vapor which fills the hollow antenna and maintains it at an elevated temperature to prevent formation of ice on the antenna and bushing.

The heater 24 can be formed as part of the bushing 17 or as a separate unit. Various other changes and modifications may be made within the scope of the invention as set forth in the following claim.

What is claimed is:

An antenna comprising; an electrical conductor embodying an hermetically sealed fluid holding duct containing a halogenated hydrocarbon fluid, part of said conductor requiring freedom from snow and ice and containing a portion of said duct so arranged as to receive vapor from and drain liquid to a second part of the duct, and a heater arranged to apply heat to said second part.

References Cited in the file of this patent UNITED STATES PATENTS 529,304 Perkins Nov. 13, 1894 1,676,068 Bayer July 13, 1928 1,904,140 Hentschel Apr. 19, 1933 1,904,771 Hentschel Apr. 19,1933 2,007,007 Snell July 2, 1935 2,142,117 Dow Jan. 3, 1939 2,237,054 Jensen Apr. 1, 1941 2,285,588 Kirkes June 9, 1942 2,678,374 Jones et al May 11, 1954 2,760,191 Blackmer et a1 Aug. 21, 1956 FOREIGN PATENTS 326,309 Germany Sept. 24, 1920 

